Regional Differentiation of GDP at the NUTS-3 Level in Selected European Countries after their Accession to the European Union

The issue of regional development is gaining importance due to the disproportions in its socio-economic aspects. The study aims to identify changes in economic development of selected countries which joined the European Union (EU) in 2004. The study examines small NUTS-3 (Nomenclature of territorial units for statistics) regions, which are territories determined for statistical purpose, that are less often analysed in the literature. Moreover, it focuses on spatial aspects, also considering rarely examined urban-rural typology of regions. The value and dynamics of gross domestic product (GDP) changes were presented using the Eurostat data for 2004-2019 on GDP per capita ratio (PPS) and GDP per capita (in % in relation to the EU-28 average). The analysis uses basic statistical and convergence measures; regional disparities were presented on graphs and maps. It was found that the examined EU countries are internally different in terms of economic development. The growth of GDP per capita was most dynamic in the Baltic States, Slovakia and Poland. The dynamics of GDP per capita in relation to the EU average was higher in regions - regardless of the type - where the value of GDP per capita was lower at the time of accession to the EU. In rural regions, the dynamics of development changes was smaller in relation to other types of regions. Convergence (both beta and sigma) is occurring at a very low level. Further research may focus on the reasons for enclosed disparities and factors of the ongoing changes.